The primary term goal of these research efforts has been to enhance the functional status, comfort and quality of life of edentulous patients by evaluating clinical procedures, denture designs and adjunctive therapies based upon a clear understanding of: (1) oral functional impairments caused by the loss of teeth and subsequent tissue changes; (2) neurophysiological mechanisms associated with oral functions; (3) metabolism of oral tissues; and (4) interactions between biological and psychological processes and denture characteristics. The primary purpose of the proposed clinical outcome study is to compare the relative efficacies of three different combinations of implant-supported maxillary and mandibular prostheses with traditional complete dentures for edentulous patients. Completion of this study will determine the relative cost-effectiveness of the implant-supported denture treatments for use in the general population of edentulous patients.